#ifndef Nil_HEADER_H 
#define Nil_HEADER_H


#include "../SQLEvalVisitor.h"
// #include "SQLEvalVisitorUtils.h"
#include "../../ast/SQLExpr.h"
#include "../../ast/expr/SQLMethodInvokeExpr.h"
#include "../../parser/ParserException.h"
#include "Function.h"

class Nil : virtual public SQLFunction {
	public:
		static Nil *instance();
		virtual ~Nil();
		virtual Object_ptr eval(SQLEvalVisitor *visitor, SQLMethodInvokeExpr *x);

};
#endif

